"How did they do it 145 years ago?​

Actually not much different than we do today. Just as with the cartridge itself, even this can be a tad complicated. Do not forget this is Winchester's first "center fire cartridge that can be reloaded many times". With this, we need the tools and reloading components. Winchester came out with the cartridge in 1873' but we don't seem to see handloading equipment until at least 1875.